The brain of physicist Albert Einstein has been a subject of much research and speculation. Einstein's brain was removed within seven and a half hours of his death. The brain has attracted attention because of Einstein's reputation as one of the foremost geniuses of the 20th century, and apparent regularities or irregularities in the brain have been used to support various ideas about correlations in neuroanatomy with general or mathematical intelligence. Scientific studies have suggested that regions involved in speech and language are smaller, while regions involved with numerical and spatial processing are larger. Other studies have suggested an increased number of glial cells in Einstein's brain. wrote: